Microbial invasion into the ocular surface (OS) compromises corneal clarity and causes inflammation in blinding conditions like keratitis, endoophthalmitis and trachoma. However, in many cases the pathogen(s) remains unidentified because it fails to grow in culture. In this project we will utilize latest DNA sequencing technology to overcome this limitation. Our ultimate goal is to investigate the role of commensal microbial population of the human OS in health and disease. Our approach is to use the "culture-independent" technology that detects and assigns non-human DNA to taxonomically distinct microbial species. The same technology in combination with bioinformatics will be utilized to annotate microbial genes to functional pathways, in order to determine potential activity of microbial population on the OS. We will analyze samples of healthy conjunctiva and corneas to examine differences in microbial communities ("microbiome") in different compartments of ocular surface. We put forth a coordinated effort of multidisciplinary team at Bascom Palmer Eye Institute and microbial genomics experts at the Argonne National Laboratory (Argonne, IL) to investigate, for the first time, the OS microbiome. The new knowledge acquired in this project is expected to revolutionize the understanding of ocular ocular microbial ecology, and facilitate designing of novel diagnostic tools. Successful completion of this project will advance the field towards testing the therapeutic potential of manipulation the OS microbiome. PUBLIC HEALTH RELEVANCE: The ultimate goal of this new project is recruit new sequencing technology to detect, identify and catalogue all microorganisms that populate human ocular surface, and can potentially affect vision. We will undertake the first comprehensive characterization of microbial diversity of healthy ocular surface that will allow us to monitor bacterial diversity in healthy and diseased eyes. Successful completion of this project will bring to a new level both diagnostics and understanding of ocular infections. PHS 398/2590 (Rev. 09/04, Reissued 4/2006) Page Continuation Format Page